Comparing the training and test sets, there were significant differences in race, DAS28-ESR at baseline, SJC28, TJC28, ESR, PtGA, PhGA, glucocorticoid use, HAQ, RA duration, and proportion of good responders; no significant differences were observed in age, sex, CRP, RF status, and ACPA status (Table 1). This evidence concerns the gene CRP and rheumatoid arthritis.